Thermometer for incubators.



No. 767,493. PATENTED AUG. 16, 1904,

A. NEUBBC K.

THERMOMETER FOR INGUBATORS. APPLICATION rum) NOV. 2, 1903.

N0 MODEL L W HIGH INV NTOR A; ATTORNEY IlNrran STATES Patented August16, 1904.

ATENT @rrrce.

THERMOIVIETER FOR INCUBATORS.

SPECIFICATION forming part of Letters Patent No. 767,493, dated. August16, 1904.

Application filed November 2, 1903. Serial No. 179,511. (No model.)

To all whom it ntcty concern:

Be it known that I, AUGUST N EUBECK, a citizen of the United States ofAmerica, and a resident of New York, borough of Brooklyn, county ofKings, State of New York, have invented certain new and usefulImprovements in Thermometers for Incubators, of which the following is aspecification.

This invention has reference to thermometers, and pertains particularlyto that class of thermometers which are filled with a liquid which isusually colored and of low specific gravity.

It is the special object of this invention to produce a thermometer ofthe class described which is particularly adapted for use in incubators,and therefore the scale of the thermometer is preferably from 90 to 110Fahrenheit. Thermometers of this kind which have a limited scalestarting at a relatively high point, in this instance at 90 Fahrenheit,are so constructed that the tube is not too long. Therefore the quantityof liquid introduced therein is such as to bring the liquid up to thescale in a rather short tube. For this reason the liquid in thethermometer when the latter is not in use and in a rather cool placereturns completely into the bulb, and if from any cause whatsoever atrace of air is left in the thermometer then same is certainly found onthe highest point of the bulb. Upon expansion of the liquid this air isinclosed there and causes disturbances when the liquid further expandsup into the capillary tube, and incorrectness in the readings is anotherresult therefrom. This of course is particularly the case withthermometers having their bulbs in a position other than the verticalone usually employed.

In order to avoid the described deficiencies in thermometers of theclass above mentioned, I have provided a new thermometer-bulb for same,and particularly for thermometers to be used in incubators forcontrolling the temperature therein during the artificial hatching ofeggs.

The invention is illustrated in the accompanying drawings, in whichFigure 1 shows a complete thermometer in front elevation which embodiesmy invention.

Fig. 2 is a cross-section of the thermometerbulb. Fig. 3 represents amodification of the thermometer-bulb, and Fig. 4 illustrates a plainscale.

Similar characters of reference denote like parts in all the figures.

. In the drawings, (0 represents the thermometer-bulb. b is thecapillary tube, and c the scale.

In the present invention the bulb blown onto the capillary tube differsfrom the bulbs heretofore employed. Instead of a plain bulb I haveprovided a bulb which has inside an extra tube (Z. This tube extendswithin the bulb according to requirement, in some instances reachingdown to almost the roundedoff end a of same. The tube (Z is joined tothe bulb a at the point where the capillary tube is joined thereto bythe fusion of the glass. The capillary opening of the tube?) coincideswith the opening of the inside tube (Z, which is open at its end f.Hereby the capillary opening in the tube 6 and the opening in the insidetube (Z communicate with the space 9 of thebulb. As shown in Figs. 1, 2,and 3, the capillary tube is bent under a sharp angle near the bulb, sothat the latter practically rests in a horizontal position when thethermometer is in use.

Assuming now that the thermometer has been finished and before sale orafter use is subjected to cold, so that the liquid contracts to such adegree as to be completely contained within the bulb, then any trace ofair which may be in the capillary tube above the liquid can never reachthe point c' of the bulb. This is impossible, because before any traceof air can reach the bulb a it would have to travel through the entirelength of the inside tube (Z. In no instance will the contraction of theliquid be so great that the latter will retreat down to the open end fof the inside tube (Z. Upon reexpansion of the liquid any trace of airis forced up into the capillary tube before the liquid and cannot dividethe column of liquid in the capillary bore. In this way not only areliable instrument is obtained, but also a correct one. If there were abubble of air either in the thermometer-bulb or between the column ofliquid in the capillary bore, the

thermometer would not be lost; but it would have to be sent back to themanufacturer to be fixed up again. It is plainly seen that the insidetube (Z guards against the described deliciencies without materiallyincreasing the cost of the instrument.

The modification of the bulb shown in Fig. 3 differs from the bulbillustrated in Fig. 2, in so far as its open end 911. is flattened outand is funnel-shaped. In this form the open end m nearly fills up theinside space of the bulb a. This funnel-shaped open end m helps tofacilitate the filling of the thermometer during its manufacture. Thebulb is, as usual, first heated and partially filled. Then it is heatedagain, and the vapors of the boiling liquid expel the air from the bulb.Upon cooling the bulb will be gradually filled. However, it happensquite often that then a hubble is still contained in the bulb. Byskilful manipulation this bubble of air is allowed to escape through theopening in the tube (Z. The funnel-shaped end of the tube (Z greatlyfacilitates this, because it presents a larger surface to the escapingair-bubble.

The scale of the thermometer ranges from to Fahrenheit. In additionthereto the word Low is found under the line indicatinglOO Fahrenheitand the word High under the line indicating Fahrenheit. Above the lineindicating 103 Fahrenheit there is a small chicken, which indicates thatthis is the best temperature for the artificial hatching of eggs. Thetwo words and the little chicken are put thereon to make work easier forthe attendants. It shows that the temperature of the incubator shouldnever fall below 100 Fahrenheit and never rise above 105" Fahrenheit. Ifpossible, the temperarenheit.

Fig. 1 is made this way for practical reasons. I do not, however, limitmyself to this shape of scale. A plain scale, as illustrated in Fig. 4:,may likewise be used, the principal feature of the invention being thenovel bulb characterized by the inside tube.

The liquid employed in these thermometers may be colored alcohol or acomposition of which alcohol is a principal component.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. A thermometer for use in incubators comprising abulb filled with a colored liquid, an inside tube in said bulbjoinedthereto by the fusion of the glass and having a funnel-shaped open end,and a capillary tube joined to the bulb by fusion, in combination with ascale ranging about from 90 to Fahrenheit.

2. A thermometer for use in incubators comprising an elongatedbulbfilled with a colored liquid of low specific gravity, an inside tubein said bulb joined thereto by the fusion of the glass and having afunnel-shaped open end, and a capillary tube joined to the bulb byfusion and bent under a sharp angle near said bulb, in combination witha scale ranging about from 90 to 110 Fahrenheit.

3. In a thermometer for use in incubators, an elongated bulb for theexpanding colored liquid of low specific gravity, an inside tube in saidbulb joined thereto by the fusion of the glass and having afunnel-shaped open end, and a capillary tube joined to the bulb and bentunder a sharp angle near said bulb.

Signed at New York, N. Y., this 31st day of October, 1903.

AUGUST NEUBEGK.

Witnesses: H

JAMEs J. .ASYITARITA, HA'rTIn l Lnunens.

